code: def test_chrf_empty_functional():
      """Test that eed returns 0 when no input is provided."""
      preds = []
      targets = [[]]
      assert chrf_score(preds, targets) == tensor(0.0)
  
file_path: torchmetrics/tests/unittests/text/test_chrf.py
imports: from functools import partial
  from typing import Sequence
  import pytest
  from torch import Tensor, tensor
  from torchmetrics.functional.text.chrf import chrf_score
  from torchmetrics.text.chrf import CHRFScore
  from torchmetrics.utilities.imports import _SACREBLEU_AVAILABLE
  from unittests.text.helpers import TextTester
  from unittests.text.inputs import _inputs_multiple_references, _inputs_single_sentence_multiple_references
label_desc: Use image node_id 2 for calling a global function with example usage: test_chrf_empty_functional() without return types